Question 1

Which of the following statements about the Hardy-Weinberg equilibrium is true?

Accepted Answer

A)  It explains why dominant alleles do not necessarily replace recessive alleles in a population. 
B)  It applies only to populations in which there is gene flow. 
C)  It assumes that populations are small. 
D)  It assumes that individuals prefer to mate with individuals with certain genotypes. 
E)  None of the above 
A)  It explains why dominant alleles do not necessarily replace recessive alleles in a population. 
B)  It applies only to populations in which there is gene flow. 
C)  It assumes that populations are small. 
D)  It assumes that individuals prefer to mate with individuals with certain genotypes. 
E)  None of the above

Question 2

Evolutionary changes in the _______ protein on the surface of the influenza virus allow the virus to circumvent detection by our immune system.

Accepted Answer

The answer of Evolutionary changes in the _______ protein on...

Question 3

Under Hardy-Weinberg equilibrium, if the frequency of one allele is 0.7 and the frequency of the other allele is 0.3, then _______ of the population should be heterozygotes.

Accepted Answer

The answer of Under Hardy-Weinberg equilibrium, if the frequency of...

Question 4

Which of the following statements about mutations is false?

Accepted Answer

A)  Mutation rates are very low for most loci. 
B)  Mutations are random with respect to the adaptive needs of organisms. 
C)  Most mutations are either harmful or neutral. 
D)  Only rarely does a human carry a new mutation in his or her genome. 
E)  The current human population carries billions of new mutations that were not present in previous generations. 
A)  Mutation rates are very low for most loci. 
B)  Mutations are random with respect to the adaptive needs of organisms. 
C)  Most mutations are either harmful or neutral. 
D)  Only rarely does a human carry a new mutation in his or her genome. 
E)  The current human population carries billions of new mutations that were not present in previous generations.

Question 5

The graph below shows the range of variation among population members for a trait determined by multiple genes.   If this population is subject to stabilizing selection for several generations, which of the distributions would be most likely to result?

Accepted Answer

A)   
B)   
C)   
D)   
E)  Both a and b 
A)   
B)   
C)   
D)   
E)  Both a and b

Question 6

Mutations

Accepted Answer

A)  are any change in an organism's DNA. 
B)  occur at high frequencies. 
C)  are not inherited. 
D)  maintain and generate genetic diversity. 
E)  Both a and d 
A)  are any change in an organism's DNA. 
B)  occur at high frequencies. 
C)  are not inherited. 
D)  maintain and generate genetic diversity. 
E)  Both a and d

Question 7

Which of the following is a plausible explanation for the typically slow rates of evolution over the long term?

Accepted Answer

A)  Most populations have little genetic variation. 
B)  Natural selection is typically a stabilizing phenomenon. 
C)  Directional selection is commonplace. 
D)  Genetic drift counters the effects of selection, particularly in large populations. 
E)  Mutation rates are very high. 
A)  Most populations have little genetic variation. 
B)  Natural selection is typically a stabilizing phenomenon. 
C)  Directional selection is commonplace. 
D)  Genetic drift counters the effects of selection, particularly in large populations. 
E)  Mutation rates are very high.

Question 8

Suppose that a particular species of flowering plant that lives only one year can produce red, white, or pink blossoms, depending on its genotype. Biologists studying a population of this species count 300 red-flowering, 500 white-flowering, and 800 pink-flowering plants in a population. When a census of the population is taken the following year, 600 red-flowering, 900 white-flowering, and 1,000 pink-flowering plants are observed. Which color has the highest fitness?

Accepted Answer

A)  Red 
B)  White 
C)  Pink 
D)  All colors are equally fit. 
E)  The answer cannot be determined from this information. 
A)  Red 
B)  White 
C)  Pink 
D)  All colors are equally fit. 
E)  The answer cannot be determined from this information.

Question 9

Which of the following statements about population bottlenecks is false?

Accepted Answer

A)  They are an extreme example of genetic drift. 
B)  They can result in changes in allele frequencies. 
C)  They can result in the loss of genetic variation. 
D)  They arise from severe reductions in population size. 
E)  All of the above are true; none is false. 
A)  They are an extreme example of genetic drift. 
B)  They can result in changes in allele frequencies. 
C)  They can result in the loss of genetic variation. 
D)  They arise from severe reductions in population size. 
E)  All of the above are true; none is false.

Question 10

Laboratory selection experiments with fruit flies have demonstrated that

Accepted Answer

A)  bristle number is not genetically controlled. 
B)  bristle number is not genetically controlled, but changes in bristle number are caused by the environment in which the fly is raised. 
C)  bristle number is genetically controlled, but there is little variation on which natural selection can act. 
D)  bristle number is genetically controlled, but selection cannot result in flies having more bristles than any individual in the original population had. 
E)  bristle number is genetically controlled, and selection can result in flies having more, or fewer, bristles than any individual in the original population had. 
A)  bristle number is not genetically controlled. 
B)  bristle number is not genetically controlled, but changes in bristle number are caused by the environment in which the fly is raised. 
C)  bristle number is genetically controlled, but there is little variation on which natural selection can act. 
D)  bristle number is genetically controlled, but selection cannot result in flies having more bristles than any individual in the original population had. 
E)  bristle number is genetically controlled, and selection can result in flies having more, or fewer, bristles than any individual in the original population had.

Question 11

Which of the following is an adaptation?

Accepted Answer

A)  The lion's speed, which enables the animal to capture its prey 
B)  The process by which a lion's speed increases over many generations 
C)  Differential survival 
D)  Both a and b 
E)  Both b and c 
A)  The lion's speed, which enables the animal to capture its prey 
B)  The process by which a lion's speed increases over many generations 
C)  Differential survival 
D)  Both a and b 
E)  Both b and c

Question 12

Following a flood, migration from neighboring populations alters genotypic frequencies of a population of river-bottom midges. Assuming that the conditions for Hardy-Weinberg subsequently are met, how many generations of random mating are required to restore the genotypic frequencies to Hardy-Weinberg equilibrium?

Accepted Answer

A)  1 
B)  2 
C)  Between 3 and 10 
D)  Between 11 and 20 
E)  More than 20 
A)  1 
B)  2 
C)  Between 3 and 10 
D)  Between 11 and 20 
E)  More than 20

Question 13

Use the following to answer questions:
Refer to the graph below, showing beak size for a population of a species of Darwin's finches.  
-Draw a graph showing what the resulting population would look like after a generation of directional selection for smaller beak size.

Accepted Answer

The answer of Use the following to answer questions:
Refer to...

Question 14

Use the following to answer questions:
In a population of 200 individuals, 72 are homozygous recessive for the character of eye color (cc). One hundred individuals from this population die from a fatal disease. Thirty-six of the survivors are homozygous recessive.
-In the original population, the frequency of the dominant allele is

Accepted Answer

A)  0.16. 
B)  0.36. 
C)  0.40. 
D)  0.48. 
E)  0.60. 
A)  0.16. 
B)  0.36. 
C)  0.40. 
D)  0.48. 
E)  0.60.

Question 15

The phenotype of an organism is

Accepted Answer

A)  the type specimen of its species in a museum. 
B)  its genetic constitution, which governs its traits. 
C)  the chronological expression of its genes. 
D)  the physical expression of its genotype. 
E)  its adult form. 
A)  the type specimen of its species in a museum. 
B)  its genetic constitution, which governs its traits. 
C)  the chronological expression of its genes. 
D)  the physical expression of its genotype. 
E)  its adult form.

Question 16

In comparing several populations of the same species, the population with the greatest genetic variation would have the

Accepted Answer

A)  greatest number of genes. 
B)  greatest number of alleles per gene. 
C)  greatest number of population members. 
D)  largest gene pool. 
E)  None of the above 
A)  greatest number of genes. 
B)  greatest number of alleles per gene. 
C)  greatest number of population members. 
D)  largest gene pool. 
E)  None of the above

Question 17

Use the following to answer questions:
Suppose you have a population of flour beetles with 1,000 individuals. Normally the beetles are red; however, this population is polymorphic for a mutant autosomal body color, black, designated by b/b. Red is dominant to black, so B/B and B/b genotypes are red. Assume the population is in Hardy-Weinberg equilibrium, with equal frequencies of the two alleles.
-What would be the expected frequencies of the red and black phenotypes?

Accepted Answer

A)  0.5 red; 0.5 black 
B)  0.75 red; 0.25 black 
C)  0.25 red; 0.75 black 
D)  0 
E)  Insufficient information is given to answer the question. 
A)  0.5 red; 0.5 black 
B)  0.75 red; 0.25 black 
C)  0.25 red; 0.75 black 
D)  0 
E)  Insufficient information is given to answer the question.

Question 18

Use the following to answer questions :
The following data were collected in a study in which dark and light moths of the peppered moth (Biston betularia) were released and recaptured a few days later in several different areas (a, b, c, and d).  
-As peppered moths rest on bark surfaces during the day, they are subject to predation by birds. If one can assume that moths that are more camouflaged will be preyed on less, what would be the likely color of bark surfaces in area d?

Accepted Answer

Dark moths seem to survive bes

Question 19

Deviations from the Hardy-Weinberg equilibrium in populations

Accepted Answer

A)  are very rare. 
B)  suggest that mechanisms exist in nature that can change the frequency of alleles. 
C)  are evidence for evolution. 
D)  can help in the identification of the mechanisms of evolution. 
E)  b, c, and d 
A)  are very rare. 
B)  suggest that mechanisms exist in nature that can change the frequency of alleles. 
C)  are evidence for evolution. 
D)  can help in the identification of the mechanisms of evolution. 
E)  b, c, and d

Question 20

A main goal of the field of _______ is to explain the origin and maintenance of genetic variation.

Accepted Answer

The answer of A main goal of the field of...

Exam 21: Evidence and Mechanisms of Evolution

Which of the following statements about the Hardy-Weinberg equilibrium is true?

Evolutionary changes in the _______ protein on the surface of the influenza virus allow the virus to circumvent detection by our immune system.

Under Hardy-Weinberg equilibrium, if the frequency of one allele is 0.7 and the frequency of the other allele is 0.3, then _______ of the population should be heterozygotes.

Which of the following statements about mutations is false?

The graph below shows the range of variation among population members for a trait determined by multiple genes. If this population is subject to stabilizing selection for several generations, which of the distributions would be most likely to result?

Mutations

Which of the following is a plausible explanation for the typically slow rates of evolution over the long term?

Which of the following statements about population bottlenecks is false?

Laboratory selection experiments with fruit flies have demonstrated that

Which of the following is an adaptation?

Use the following to answer questions: Refer to the graph below, showing beak size for a population of a species of Darwin's finches. -Draw a graph showing what the resulting population would look like after a generation of directional selection for smaller beak size.

The phenotype of an organism is

In comparing several populations of the same species, the population with the greatest genetic variation would have the

Deviations from the Hardy-Weinberg equilibrium in populations

A main goal of the field of _______ is to explain the origin and maintenance of genetic variation.

Studying Life

Small Molecules and the Chemistry of Life

Proteins, Carbohydrates, and Lipids

Nucleic Acids and the Origin of Life

Cells: the Working Units of Life

Cell Membranes

Cell Signaling and Communication

Energy, Enzymes, and Metabolism

Pathways That Harvest Chemical Energy

Photosynthesis: Energy From Sunlight

The Cell Cycle and Cell Division

Inheritance, Genes, and Chromosomes

Dna and Its Role in Heredity

From Dna to Protein: Gene Expression

Gene Mutation and Molecular Medicine

Regulation of Gene Expression

Genomes

Recombinent Dna and Biotechnology

Differential Gene Expression in Development

Development and Evolutionary Change

Reconstructing and Using Phylogenies

Species and Their Formation

Evolution of Genes and Genomes

The History of Life on Earth

Bacteria and Archaea: the Prokaryotic Domains

The Origin and Diversification of Eukaryotes

Plants Without Seeds: From Water to Land

The Evolution of Seed Plants

Fungi: Recyclers, Pathogens, Parasites, and Plant Partners

Animal Origins and the Evolution of Body Plans

Protostome Animals

Deuterostome Animals

The Plant Body

Transport in Plants

Plant Nutrition

Regulation of Plant Growth

Reproduction in Flowering Plants

Plant Responses to Environmental Challenges

Physiology, Homeostasis, and Temperature Regulation

Animal Hormones

Immunology: Animal Defense Systems

Animal Reproduction

Animal Development

Neurons and Nervous Systems

Sensory Systems

The Mammalian Nervous System: Structure and Higher Function

Musculoskeletal Systems

Gas Exchange in Animals

Circulatory Systems

Nutrition, Digestion, and Absorption

Salt and Water Balance and Nitrogen

Animal Behavior

Ecology and the Distribution of Life

Population Ecology

Species Interaction and Coevolution

Community Ecology

Ecosystems and Global Ecology

Conservation Biology

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